This indicates that the panel has been manufactured to dimensions that help accommodate recommended panel end and edge spacing when installed.
Plywood: Span rating
OSB: Span rating
Plywood: Formaldehyde
OSB: Formaldehyde
Plywood: Concrete Formwork
Plywood: Tongue & Groove
OSB: Tongue & Groove
Plywood: Sized for Spacing
OSB: Sized for Spacing
Plywood: Span rating
OSB: Span rating
Plywood: Span rating
OSB: Span rating
Plywood: Glue Bond Durability
OSB: Exposure Durability